performance - Linux memory usage: Can we consider memory full when swap is unused? -

-

i checking available free memory after deploying our applications. using below command , finding free memory less 20%:

free | grep mem | awk '{print "free memory :"100*($4+$6+$7)/$2"%"}'

but when check top command, see swap memory not used @ all. above command doesn't include swap memory space. have several questions in mind

snapshot1:

 top - 10:01:07 305 days, 11:23,  1 user,  load average: 0.35, 0.22, 0.12 tasks: 244 total,   1 running, 242 sleeping,   0 stopped,   1 zombie cpu(s): 13.4%us, 14.5%sy,  0.0%ni, 69.3%id,  0.8%wa,  0.4%hi,  1.6%si,  0.0%st mem:     15952m total,    15817m used,      135m free,      531m buffers swap:    16378m total,        0m used,    16378m free,     2567m cached    pid user      pr  ni  virt  res  shr s %cpu %mem    time+  command            19983 user1       20   0 3410m 2.9g 4420 s   23 18.9  56733:33 x1              28390 user2      20   0  621m 216m 1300 s   12  1.4  40201:39 p2                24781 user1       20   0 1393m 868m 1760 s    9  5.4  27795:12 p3           13936 user1       20   0  740m 432m 2692 s    6  2.7  15726:39 p4           30545 user1       20   0  391m  77m 2232 s    6  0.5   2805:05 p5          5696 user1       20   0  914m 680m 2180 s    4  4.3   2209:03 p6                 28801 user2      20   0  282m 148m 1432 s    4  0.9  12408:20 p7                 29559 user2      20   0  504m 357m 2028 s    3  2.2   9152:52 p8                 29129 user2      20   0  245m 172m 2004 s    2  1.1   6935:50 p9                 29130 user2      20   0  245m 172m 1996 s    2  1.1   6879:25 p9                 29131 user2      20   0  245m 172m 1996 s    2  1.1   6913:15 p9                 29135 user2      20   0  245m 172m 1996 s    2  1.1   6897:49 p9                 29140 user2      20   0  245m 172m 1996 s    2  1.1   6886:52 p9

snapshot 2:

top - 10:06:18 312 days, 11:29,  1 user,  load average: 0.26, 0.42, 0.31 tasks: 240 total,   1 running, 238 sleeping,   0 stopped,   1 zombie cpu(s): 13.1%us, 11.8%sy,  0.0%ni, 71.8%id,  1.7%wa,  0.5%hi,  1.1%si,  0.0%st mem:     15952m total,    15832m used,      119m free,      480m buffers swap:    16378m total,        0m used,    16378m free,     2622m cached    pid user      pr  ni  virt  res  shr s %cpu %mem    time+  command            19983 user1       20   0 3410m 2.9g 5292 s   18 18.9  58711:30 x1              28390 user2      20   0  621m 216m 1300 s   12  1.4  41451:12 p2                24781 user1       20   0 1393m 868m 1760 s    8  5.4  28615:15 p3           13936 user1       20   0  740m 432m 2692 s    6  2.7  16247:35 p4           12453 user1       20   0  387m  74m 3056 s    5  0.5 178:45.72 p5         28801 user2      20   0  282m 148m 1448 s    4  0.9  12794:23 p6                 13252 user1       20   0  850m 665m 2556 s    4  4.2 138:43.83 p7                 29559 user2      20   0  504m 357m 1992 s    3  2.2   9450:05 p8                 29154 user2      20   0  245m 172m 1972 s    3  1.1   7127:40 p9                 29130 user2      20   0  245m 172m 1972 s    2  1.1   7104:03 p9                 29140 user2      20   0  245m 172m 1972 s    2  1.1   7111:48 p9                 29171 user2      20   0  244m 172m 1972 s    2  1.1   7137:48 p9                 29129 user2      20   0  245m 172m 1980 s    2  1.1   7162:12 p9

am using correct method check available free space? (i need raise alarm when memory usage high)

2.from below 2 snapshots see free memory reduced "135m free" "119m free" (pls check mem: row of top command). see memory related processes (even other) not changed buffers , cache reduced. have read earlier these memory released os if enough memory not available processes. should worry change? there way clear this?

  1. my system has mem:15952m total, swap:16378m total total available space? system performance go down once swap memory starts being used?

pls guide me

example free memory output:

>free               total       used       free     shared    buffers     cached mem:       8183648    7148324    1035324          0     150568    2352956 -/+ buffers/cache:    4644800    3538848 swap:     17149376      24588   17124788


Comments

Post a Comment

Popular posts from this blog

Fail to load namespace Spring Security http://www.springframework.org/security/tags -

-
i have problem namespace of spring security on xhtml page. don't understand why can't load uri, , have following issue: whitelabel error page application has no explicit mapping /error, seeing fallback. tue jul 21 16:58:12 utc 2015 there unexpected error (type=not found, status=404). please need help! possible uri has been changed? best regards you using incorrect namespace url. correct url http://www.springframework.org/schema/security the error page seeing spring source website since not recognize url. try visiting http://www.springsource.org/security/tags in browser update : spring security tags used in jsp page correct tag lib declaration is: <%@ taglib prefix="sec" uri="http://www.springframework.org/security/tags" %>
Read more

sql - MySQL query optimization using coalesce -

-
can explain me why second query faster first? (first 1 takes around 40 seconds, second 1 less 0.1) select releases.feature_code, releases.platform_id, version, release_date, general_available, uri, filesize, display_name, feature_name.full_name, if ((select exists(select 1 release_exceptions releases.feature_code = release_exceptions.feature_code , releases.platform_id = release_exceptions.platform_id , releases.version = release_exceptions.version) = 1), 1, 0) release_exceptions releases left outer join platform using(platform_id) left outer join feature_name using(feature_code) order version desc; ~~~ query 2 ------------------ ~~~ select feature_code, version, release_date, general_available, platform_id, uri, filesize, display_name, feature_name.full_name, coalesce(release_exceptions, 0) release_exceptions mus.releases left outer join ( select distinct feature_code, version, platform_id, 1 release_exceptions mus.release_exceptions ) release_exceptions using ...
Read more

unity3d - Unity local avoidance in user created world -

-
i'm using unity3d networked multiplayer online game have large complex 3d terrain scene forest, trees, cliff, hills, mountains, bounders, etc. players can build structures sort of minecraft, , put them anywhere in scene, or move them around anytime. aside human controlled players, there automated ai players , objects animals roaming around scene following path. the problem how make these automated ai players , animals, able navigate around static , dynamic player created structures, because path follow can blocked player created structures, or other players , other ai objects, cliffs etc. have find away around them or on track if tumble down off high cliff example. so made navmesh , used navagents, takes care of static, non moving objects, how make ai players navigate around each other , dynamic structures created players can number in hundreds? i thought of adding navmeshobstacle everything, result in being attached hundreds of objects since user created structures b...
Read more